The herein described invention relates generally to a cushioning conversion machine and method for converting sheet-like stock material into a cushioning product.
In the process of shipping an item from one location to another, a protective packaging material is typically placed in the shipping case, or box, to fill any voids and/or to cushion the item during the shipping process. Some conventional protective packaging materials are plastic foam peanuts and plastic bubble pack. While these conventional plastic materials seem to adequately perform as cushioning products, they are not without disadvantages. Perhaps the most serious drawback of plastic bubble wrap and/or plastic foam peanuts is their effect on our environment. Quite simply, these plastic packaging materials are not biodegradable and thus they cannot avoid further multiplying our planet""s already critical waste disposal problems. The non-biodegradability of these packaging materials has become increasingly important in light of many industries adopting more progressive policies in terms of environmental responsibility.
The foregoing and other disadvantages of conventional plastic packaging materials have made paper protective packaging material a very popular alterative. Paper is biodegradable, recyclable and composed of a renewable resource, making it an environmentally responsible choice for conscientious industries.
While paper in sheet form could possibly be used as a protective packaging material, it is usually preferable to convert the sheets of paper into a relatively low density pad-like cushioning dunnage product. Cushioning conversion machines in use today have included a forming device and a feeding device which coordinate to convert a continuous web of sheet-like stock material (either single-ply or multi-ply) into a three dimensional cushioning product, or pad. The forming device is used to fold, or roll, the lateral edges of the sheet-like stock material inward on itself to form a strip having a width substantially less than the width of the stock material. The feeding device advances the stock material through the forming device and it may also function as a crumpling device and a connecting for assembling) device. The cushioning conversion machine may also include a ply-separating device for separating the plies of the web before passing through the former, and usually a severing assembly; for example, a cutting assembly for cutting the strip into sections of desired length.
European Patent Application No. 94440027.4 discloses a cushioning conversion machine wherein the feeding device comprises input and output pairs of wheels or rollers which operate at different speeds to effect, along with feeding of two plies of paper, crumpling and assembling of the paper plies to form a connected strip of dunnage. The cushioning conversion art would benefit from improvements in the machine shown in such application, and such improvements may have applicability to other cushioning conversion machines as well.
The present invention provides an improved cushioning conversion machine and related methodology characterized by one or more features including, inter alia, a feeding/connecting assembly which enables an operator to easily vary a characteristic, for example, the density, of the cushioning product; a feeding/connecting assembly wherein input and/or output wheels or rollers thereof are made at least in part of an elastomeric or other friction enhancing material, which reduces the cost and complexity of the input and output rollers; a manual reversing mechanism that is useful, for example, for clearing paper jams; a modular arrangement of a forming assembly and feeding/connecting assembly in separate units that may be positioned remotely from one another, as may be desired for more efficient utilization of floor space; a layering device which provides for doubling of the layers of sheet material in the converted cushioning product; a turner bar which enables alternative positioning a stock supply roll; and a volume expanding arrangement cooperative with the feeding/connecting assembly for reducing the density of the cushioning product and increasing product yield. The features of the invention may be individually or collectively used in cushioning conversion machines of various types. These and other aspects of the invention are hereinafter summarized and more fully described below.
According to one aspect of the invention, a cushioning conversion machine, for making a cushioning product by converting an essentially two-dimensional web of sheet-like stock material of at least one ply into a three-dimensional cushioning product, generally comprises a housing through which the stock material passes along a path; and a feeding/connecting assembly which advances the stock material from a source thereof along said path, crumples the stock material, and connects the crumpled stock material to produce a strip of cushioning. The feeding/connecting assembly includes upstream and downstream components disposed along the path of the stock material through the housing, at least the upstream component being driven to advance the stock material toward the downstream component at a rate faster than the sheet-like stock material can pass from the downstream component to effect crumpling of the stock material therebetween to form a strip of cushioning. Additionally, at least one of the upstream and downstream components includes opposed members between which the stock material is passed and pinched by the opposed members with a pinch pressure; and a tension control mechanism is provided for adjusting the amount of pinch pressure applied by the opposed members to the stock material. In one embodiment of the invention, the tension control mechanism includes an accessible control member outside the housing for enabling easy operator adjustment of the pinch pressure, whereby a characteristic of the strip of cushioning can be varied on demand. In another embodiment, the upstream and downstream components each include opposed members between which the stock material is passed and pinched by the opposed members with a pinch pressure; and a tension control mechanism is provided for adjusting the amount of pinch pressure applied to the stock material by the opposed members of the downstream component independently of the pinch pressure applied to the stock material by the opposed members of the upstream component, whereby a characteristic of the strip of cushioning can be varied.
According to another aspect of the invention, a cushioning conversion machine again generally comprises a housing through which the stock material passes along a path; and a feeding/connecting assembly which advances the stock material from a source thereof along the path, crumples the stock material, and connects the crumpled stock material to produce a strip of cushioning. The feeding/connecting assembly includes upstream and downstream feeding components disposed along the path of the stock material through the housing, the upstream feeding component being driven to advance the stock material toward the downstream component at a rate faster than the sheet-like stock material can pass from the downstream component to effect crumpling of the stock material therebetween to form the strip of cushioning. An adjustable speed control mechanism is provided for varying the ratio of the feeding speeds of the upstream and downstream feeding components, whereby a characteristic of the strip of cushioning can be varied. In a preferred embodiment, the adjustable speed control mechanism can include, for example, a variable speed drive device (such as a variable pitch pulley system) for one of the upstream and downstream components, a quick change gear set, or a variable speed control for at least one of respective drive motors for the upstream and downstream components. Preferably, a control member is provided outside the housing for enabling easy operator adjustment of the speed ratio, whereby a characteristic of the strip of cushioning can be varied on demand.
According to a further aspect of the invention, a cushioning conversion machine again generally comprises a housing through which the stock material passes along a path; and a feeding/connecting assembly which advances the stock material from a source thereof along the path, crumples the stock material, and connects the crumpled stock material to produce a strip of cushioning. The feeding/connecting assembly includes upstream and downstream components disposed along the path of the stock material through the housing, at least the upstream component being driven to advance the stock material toward the downstream component at a rate faster than the sheet-like stock material can pass from the downstream component to effect crumpling of the stock material therebetween to form a strip of cushioning. Also provided is a stretching component downstream of the downstream component that is operative to advance the strip of cushioning at a rate faster than the rate at which the stock material passes from the downstream component to effect longitudinal stretching of the strip of cushioning.
According to yet another aspect of the invention, a cushioning conversion machine again generally comprises a housing through which the stock material passes along a path; and a feeding/connecting assembly which advances the stock material from a source thereof along the path, crumples the stock material, and connects the crumpled stock material to produce a strip of cushioning. The feeding/connecting assembly includes upstream and downstream components disposed along the path of the stock material through the housing, at least the upstream component being driven to advance the stock material toward the downstream component at a rate faster than the sheet-like stock material can pass from the downstream component to effect crumpling of the stock material therebetween to form a strip of cushioning. At least one of the upstream and downstream components includes opposed members between which the stock material is passed and pinched by the opposed members with a pinch pressure; and at least one of the opposed members is at least partially made of an elastomeric material at a surface thereof engageable with the stock material.
According to a still further aspect of the invention, a cushioning conversion machine generally comprises a housing through which the stock material passes along a path; and a feeding/connecting assembly which advances the stock material from a source thereof along the path, crumples the stock material, and connects the crumpled stock material to produce a strip of cushioning. The feeding/connecting assembly includes at least one rotatable member rotatable in a first direction for engaging and advancing the stock material along the path, a feed motor for driving the one rotatable member in the first direction, and a crank coupled to the rotatable member for enabling rotation of the one rotatable member in a second direction opposite the first direction. In a preferred embodiment the crank is coupled to the rotatable member by a one-way clutch.
According to Vet still another aspect of the invention, a cushioning conversion machine comprises first and second units having separate housings whereby the first and second units can be located at spaced apart locations. The first unit includes in the housing thereof a former for folding the sheet-like stock material to form flat folded stock material having a plurality of layers each joined at a longitudinally extending fold to at least one other layer. The second unit includes in the housing thereof an expanding device operative, as the flat folded stock material passes therethrough, to separate adjacent layers of the flat folded stock material from one another to form an expanded strip of stock material, and a feeding/connecting assembly which advances the stock material through the expanding device, crumples the expanded stock material passing from the expanding device, and connects the crumpled strip to produce a strip of cushioning. In a preferred embodiment, the units are used in combination with a table to form a packaging system, the table including a table top having a packaging surface. The first and second units may be both located beneath said packaging surface, and one may be supported atop the other. In alternative arrangement, the first unit may be located beneath the table top and the second unit may supported on the table top.
According to another aspect of the invention, a cushioning conversion machine generally comprises a supply assembly for supplying the sheet-like stock material; and a conversion assembly which converts the sheet-like stock material received from the supply assembly into a three-dimensional strip of cushioning. The stock supply assembly includes a support for a supply of the stock material from which the stock material can be dispensed, and a layering device which effects folding of the stock material along a fold line parallel to the longitudinal axis of the stock material, thereby in effect doubling the number of layers of the stock material that are converted into a cushioning product.
According to a further aspect of the invention, a cushioning conversion machine comprises a forming assembly through which the sheet-like stock material is advanced to form the stock material into a three-dimensional shape and a feeding/connecting assembly that advances and crumples the formed strip, and connects the crumpled formed strip to produce a strip of cushioning. The forming assembly includes a forming member and a converging chute cooperative with the forming member to cause inward rolling of the edges of the stock material to form lateral pillow-like portions of a formed strip, and the feeding/connecting assembly includes upstream and downstream components disposed along the path of the stock material through the machine, at least the upstream component being driven to advance the stock material toward the downstream component at a rate faster than the sheet-like stock material can pass from the downstream component to effect crumpling of the stock material therebetween to form a strip of cushioning.
According to yet another aspect of the invention, a cushioning conversion machine comprises a feeding/connecting assembly which advances the stock material from a source thereof along a path through the machine, crumples the stock material, and connects the crumpled stock material to produce a strip of cushioning. The feeding/connecting assembly includes upstream and downstream feeding components disposed along the path of the stock material through the housing, the upstream feeding component being driven continuously to advance continuously the stock material toward the downstream feeding component during a cushioning formation operation, and the downstream feeding component being driven intermittently to advance periodically the stock material. Accordingly, when the downstream feeding component is not driven the stock material will be caused to crumple longitudinally between the upstream and downstream feeding components, and when driven the longitudinally crumpled stock material will be advanced by the downstream feeding component toward an exit end of the machine.
According to a still further aspect of the invention, a method for making a cushioning product, by converting an essentially two-dimensional web of sheet-like stock material of at least one ply into a three-dimensional cushioning product, generally includes the steps of supplying the stock material, and using an upstream component of a feeding/connecting assembly to advance the stock material toward a downstream component of the feeding/connecting assembly at a rate faster than the stock material can pass from the downstream component to effect crumpling of the stock material therebetween to form the strip of cushioning, the upstream and downstream components including opposed members between which the stock material is passed and pinched by the opposed members with a pinch pressure. In one embodiment, the method includes the step of adjusting the amount of pinch pressure applied by the opposed members of the downstream component independently of the pinch pressure applied to the stock material by the opposed members of the upstream component to the stock material, whereby a characteristic of the strip of cushioning can be varied. In another embodiment, the method includes the step of varying the ratio of the feeding speeds of the upstream and downstream feeding components, whereby a characteristic of the strip of cushioning can be varied.
The foregoing and other features of the invention are hereinafter fully described and particularly pointed out in the claims, the following description and the annexed drawings setting forth in detail certain illustrative embodiments of the invention, these being indicative, however, of but a few of the various ways in which the principles of the invention may be employed.